Explosive compound.



esparto fiber by passing NITED STATES Fries.

P TENT EXPLOSlVE COMPOUND.

SPECIFICATION forming part of Letters Patent no.

Application filedDecember 17, 1898- To all whom it may concern:

Be it known-that I, CHARLES FRIDRICH HENGsT, engineer, a subject of the Queen of Great Britain, residing at No. Burwash road, Plumstead, London, in the county of Kent, England, have invented new and useful Improvements in Explosive Compounds for War and other Purposes, of which the following is a specification.

In carrying my invention into effect I prepare in a suitable receptacle a bath containing two parts sulphuric acid, (1 1 80 specific gravity 1.85 at 18 centigrade, one part of nitric acid, (HNO from 1.42 to 1.5 specific gravity at 18 centigrade, mixed together and agitated by mechanical means or by manual power. The process of mixing these acids in the manner-stated causes the temperature of the resultant liquid to rise, and a certain amount of ebullilion takes place. The bath is allowed to stand until such ebullition ceases and the temperature has fallen to the normal condition of the atmosphere. I then prepare the grass through a disintegrator until the mass is separated into a woolly or fiuffy consistence, not bleached, since chlorine or the like tends to deterioratethe explosive. The esparto fiber so prepared is then immersed in the bath hereinbefore described when the temperature thereof is normal, a suhicient quantity being added to make a pulp, which is left to macerate from five to twenty-four hours,a'ccording to circumstances of usage and the atmospheric temperature externally. W hen the process of maceration ,is fully 'edected, the material so treated is removed from the tank or receptacle and placed in an acid-proof press, so that all the acid liquor capable of being pressed out may be so treated, the residue being washed out of the mass by continuous baths of pure water until litm'us or other acid tests are not affected. Heretofore such process has taken from two to four weeks to eliminate the acid; but I prefer to turn the pressed and partlywashed pulp into a bath containing three ounces of potassium. bicarbonate (HKCO in six gallons of water, (or in this proportion for larger quantities,) and the bath is agi- 5o tated and the boiling-point is maintained for six or eight hours,

the loss by evapora- 'ing.

640,160, dated December 26, 1899. Serial No; 699,626. (No specimens.)

tion being made up by the addition of fresh water or old sol ution. The pulp is then placed in a boiler and boiled from six to ten hours. Potassium carbonate (K 00 is-added in the proportion of 0.5 to 5 during this part of the process. I prefer to carry out the boiling operation by means of steam under pressure, since the water becomes discolored, and a fresh supply has to be provided to compensate loss by evaporation. The material is then removed to another tank or steam-boiler and treated with sufiicient hydrochloride of triamidoazobenzene (H N .G II N O H (NH to color it dark brown. Then the massis removed to a hydro-extractor or centrifugal water-separator, with a copper 'net of fine mesh, water being added during the process until the separated fluid is not colored nor is affected 'by an acid test, such as litmus or the like. At this point of manufacture the material has become of a highly-explosive nature, and great care must be exercised in drying it. I prefer to carry out the drying process by means of steam-pans subjected to steam-pressure from thirty to forty pounds per square inch, motion being imparted to. the mass during the operation to prevent oak.- This may be effected by mechanical or manual means. ;& second quantity of disintegrated pulp may be put in the acid-bath; but as the mixture has deteriorated by the first process the duration of the time of the macerating process has to be increased by one-half. Said bath may also be used athird time, with a slight addition of fresh acid.

After the pulp is dried, as describecl,I place it in an edge-running mill, previously preparing starch (G H OQn mixed with water to form a paste, with no lumps remaining, then boiling to render it of a gummy consistency, after which it is amalgamated with the pulp in the grinding-mill, about five per cent. of commercial charcoal and ten per cent. of pure potassium nitrate (KNO being added at the same time, such quantities being varied according to the conditions of usage of the explosive compound, whether for small arms, ordnance, or blasting. nance, in which a slow-burning powder is re quired, I prefer at this period of the process to add eight per cent. of one of the normal Now for large ordmass, after which it is steaming apparatus until the liquid portion has evaporated. I may I small quantity of barium nitrate, Ba(N O render the granules, blocks,

When the mass is thoroughly dry, it is der, into any required shape. Then in order to or cubesiwater and damp proof I utilize some waste material of the compositions hereinbefore described, mixing tone. or dimethyl ketone (00%83 and one.

part of benzoline or phenol, (O H 0H,) mixingthese with the waste material until it becdmes of a gummy consistence, in which the granules or blocks are dipped orotherwise This renders the ing-mach-ine, adding the acetone and phenol in quantities suflicient to dissolve the powder and render it pasty when it is cut or pressed into the desired shape. It may subsequentlybe dried bysteam,but preferably by a vacuum process, in order to recover the residual products. The granules, blocks, or the like when out, pressed, or formed resemble glass and are impervious-to moisture, and combustion during explosion is at a slow rate, giving a low pressure with a high velocity.

I may mention that in practice the first, second, and third pulps prepared in the acidbath should be mixed together in the grind- Ynited by therewith two parts of aceing process, so as to produce a uniform compoun v The explosive herein described is not igcoucussion, standing the hammer and anvil test,- is practically-smokeless when fired, and is free from nitrous or other fumes, and it does not corrode or otherwise attack the metal of a gun or the like in which it may be used.

What I claim,and desire to secure by Letters Patent of the-UnitedStates, is

The process of preparingan explosive compound consisting in the following'steps. first,

mechanicallydisintegratingesparto grass and thereby giving it while unbleached a woolly or fiufiy consistence; secondly, macerating this material for several hours in a bath consisting of a mixture of two parts of sulphuric acid and one part of nitric acid at temperature of the atmosphere'and in sufiicient quantity to make a pulp; thirdly, expressing the acid liquor and washing thereof; fourthly, boiling the mass thus'freed out the residue from acid in an aqueous solution of potassium bicarbonate for six or eight hours;-

' fifthly, coloring'the resulting material by the application of hydrochloride of triamidoazoa benzene; sixthly, washing and straining the mass until the fluid thus separated is not affected by an acidtest; seventhly,-drying the said mass; eighthly, grinding it with starch of gummy consistency and a small quantity of charcoaland potassium nitrate, until these materials are thoroughly mixed; ninthl y, dryingthe mixture,- tenthly, sifting this mafine powder; and finally a waterproof coating, substantially as set forth;

CHARLES FRIDRICH HENGST,

Witnesses:

EDMUND S. SNEWIN, WVMRO. BROWN.

and cover- 

